On site instrument transformers testing

This article presents method of on site energy measurements systems testing with special attention paid for current and voltage instrument transformers testing. The method uses modified for testing purposes three phase analyzer and tester of watthour meters type Caloprt 100. Development of extended functions allows for testing the correctness of measurement system wiring, checking the ratio error and phase error of instrument transformers and transformer burden measurement under the load conditions on site. There is described the schematic of connections by means of current clamps and then the good and bad results of wiring testing are presented with explanation of reasons. The results of burden testing are shown with description of too low, right and too high load. (On site instrument transformers testing).